Pex is a Visual Studio 2010 Power Tools that help Unit Testing .NET applications. Pex automatically generates test suites with high code coverage. Right from the Visual Studio code editor, Pex finds interesting input-output values of your methods, which you can save as a small test suite with high code coverage. Microsoft Code Digger is a Visual Studio 2012 that analyzes possible execution paths through your .NET code. The result is a table where each row shows a unique behavior of your code. The table helps you understand the behavior of the code, and it may also uncover hidden bugs.
In this blog post, Rion Williams explains how to install and use Microsoft Code Digger. It shows how Code Digger can provide the valuable inputs that the function might receive as well as the different behaviors that it might exhibit. This information can be used to find weaknesses and avoid exceptions within the code as well as to find edge cases that may remain hidden.
Read the complete blog post on http://rionscode.wordpress.com/2013/04/25/using-pex-and-microsoft-code-digger-to-better-understand-and-test-your-code/